Crank and Conrod bearings

[Jan Larsson]

So engine out (some pictures below), had to get the front clip off to reach all the way in ... not a big deal and will help as I plan to have the engine bay resprayed anyway ...

The crank bearings (see pictures) have worn down to the coppar layer as you can see, the bearings are oversize 0.010 Clevite 77 so the crank must have been machined at some point. Some scoring on the crank surface but not bad and if I run my nail over it it's near to nothing.

Conrod bearings looks really good, some embedded particles in the bearings (bearings are stock size) some light scroing but nothing bad at all looks like.

I've not checked the clearence at this point but like some adivce what I should do next, machine the crank? or just have it polished? Line honed? So any recommendations would be appreciated.

All conrods been polished (shavings removed)

 

[Jan Larsson]

And pictures of crank and crank bearings ....

 

[Jan Larsson]

Last picture

 

[Lunkan]

I guess it would be enough to polish the crank, if even needed. But that´s hard to say from a picture. But I´m not surprised to see it like that. If You plan to replace the main caps You definitely want to linehone it.

 

[Razor]

What brand of bearings are those?

Have the crank checked.. sometimes polishing may cure the surface.. sometimes not. If the crank is a STD/STD it may get polished out and you can buy .001 undersize bearings. Problem is if its a 10/10.. they dont sell .011 bearings... so it has to go to 20/20 and there lies the decision making time to get another crank.

Recently i've been using King alecular bearings and they've been holding up just fine. Theyre not as hard at the Clevite 77's and have better imbedability so they dont copper. Any trash imbeds in the bearing and doesnt scratch the crank.

FWIW, almost all OEM applications now use alecular bearings.

 

[Razor]

Last picture

Sounds like a line hone is needed.

If the coppering was even all the way across.. but appears to have a low spot there. Either trash, improper assembly, improper TQ, or improper linehone on last rebuild.

There is a dye available, my machine shop has it.. they paint the bearings and spin the crank.. it will show and high/low spots. You can also tell if you assemble the short block using oil and spin the crank. When you disassemble the bearings will show the high spots.

Now that trash had circulated the engine comes the big problem.. the oil cooler.. how do you clean it out? If it has trash in it.. as soon as you fire up the new engine.. that trash will make its way to the bearings.

Oil cooler is a discontinued item.

 

[Quiky One]

Now that trash had circulated the engine comes the big problem.. the oil cooler.. how do you clean it out? If it has trash in it.. as soon as you fire up the new engine.. that trash will make its way to the bearings.Oil cooler is a discontinued item.

Why not just get a B&M cooler and take the old one out of the loop?

Jason

 

[Jan Larsson]

Julio, the crank bearings are oversize 0.010 Clevite 77 the conrods are STD size Clevite 77 and looks good.

Line-honing is on the list for sure and at the same time they can check the crank and see what needs to be done.

Oil-Cooler is a problem of course if there's some junk in there but the oil pan had no particles to be found and the oil-cooler look really clean inside but of course those are very tiny particles ....